Tube bender



Nov. 16, 1965 J. H. STANLEY TUBE BENDER Filed Jan. 15, 1963 INVENTORJonu H. STANLEY Miami United States Patent 3,217,528 TUBE BENDER John H.Stanley, Euclid, Ohio, assignor to Parker- Hannifin Corporation,Cleveland, Ohio, at corporation of Ohio Filed Jan. 15, 1963, Ser. No.251,629 Claims. (Cl. 72-321) This invention relates to a tube bendingdevice, and in particular, to compound tube bending tool of atroublefree, simplified and highly efiicient construction.

An object of the invention is to provide a novel compound tube bendingdevice with which simple as well as complex bends may be formed in atube with an ease and rapidity heretofore incapable of being achievedwith known tube bending devices.

Another object of this invention is the provision of a novel, portable,hand-operated, compound tube bending device having a plurality of tubeengaging portions adapted to captively engage either an internal or anexternal portion of a tube to facilitate the bending of the tube.

Still another object of this invention is the provision of a novelcompound tube bending device having a reversible bracket slidablyjournalled on a handle of the tube bending device, and the reversiblebracket including two dissimilar tube engaging means at opposite endsthereof whereby either one of the two tube engaging means may be usedwhen the tube bending device is operated.

Another object of the invention is to provide a novel compound tubebending device of the type last-mentioned wherein a first of the tubeengaging means is a threaded portion which complements threads on a nutsecured to an end of the tube whereby the tube is held stationary whilethe compound tube bending device is operated to bend the tube.

Still another object of this invention is to provide a novel compoundtube bending device constructed in accordance with the above objectswherein a second of the tube engaging means is a slot and groovestructure which captively engages an external portion of the tube tohold the same immovable during the bending of the tube.

A further object of the invention is to provide a novel cooperativerelationship between the tube engaging means of the compound tubebending device constructed in accordance with the above-mentionedobjects and a sheave secured to the handle whereby a single tube can bebent at preselected portions thereof in a plurality of dissimilarplanes.

Another object of the invention is to provide a novel compound tubebending device constructed in according with the last-mentioned object,and in addition, to provide a prepositioning device lockable on thehandle of the compound tube bending device at any one of a plurality ofpositions spaced from the sheave whereby the distances between thegenerating axes of adjacent bends in a tube may be preselected.

Still another object of this invention is the provision of a novelcompound tube bending device including a tube engaging bracket-clipwhich is automatically positioned with respect to a grooved sheave ofthe device by a tube which is to be bent and requires no ancillaryclamping devices to maintain planar alignment of the tube.

A further object of this invention is to provide a novel compound tubebender constructed in accordance with the foregoing objects and inaddition, to construct the tube bender devoid of keyways and complexconnections, thereby forming a tube bender offering better supportagainst undesirable stresses during the operation thereof.

With the above, and other objects in view that will hereinafter appear,the nature of the invention will be 3,217,528 Patented Nov. 16, 1965more clearly understood by reference to the following detaileddescription, the appended claims and the several views illustrated inthe accompanying drawings.

In the drawings:

FIGURE 1 is a side view of a compound tube bending device constructed inaccordance with this invention, and illustrates a handle having agrooved sheave at one end thereof, a reversible bracket-clip providedwith tube engaging means at opposite ends thereof freely swingablymounted on the handle and spaced from the sheave by a lockableprepositioning device, and a bending arm having a grooved head at oneend thereof pivotally linked to the grooved sheave.

FIGURE 2 is a fragmentary top view of the compound tube bending deviceof FIGURE 1, and more clearly illustrates the reversible bracket-clip ofthe compound tube bending device as well as a plurality of angulargraduations on the bracketclip.

FIGURE 3 is a vertical sectional view of the compound tube bendingdevice taken along line 33 of FIGURE 1, and more clearly illustrates thevarious elements of the compound tube bending device including aswingable tube clamp in its non-use position.

FIGURE 4 is a fragmentary side view of the compound tube bending device,and shows the bracket-clip reversed end-for-end and mounted on thehandle, a threaded nut fastened to a tube in threaded engagement with athreaded portion of the bracket-clip, the swingable tube clamp in itsposition of use and the bending arm in position prior to being used tobend the tube.

A novel compound tube bending device or tube bender constructed inaccordance with this invention is best illustrated in FIGURES 1 through3 of the drawings, and is generally designated by the reference numeral10. The compound tube bending device or tube bender 10 includes anelongated handle 11 of a generally circular crosssection.

A grooved sheave 12 is secured to the elongated handle 11 by suitablemeans, not shown, such as a force fit or a threaded connection, oralternatively, the elongated handle 11 and the grooved sheave 12 may beintegrally formed.

The grooved sheave 12 includes a peripheral face 13 provided with agroove 14. The groove 14 is semi-circular in cross-section and is of adiameter substantially equal to the diameter of a tube which is to bebent by the tube bender 10. The arcuate extent of the groove 14 aboutthe periphery of the sheave 12 from a first fiat face 15 thereof to asecond flat face 16 of the sheave 12 is approximately 225, as is bestillustrated in FIGURE 1 of the drawings. A plurality of graduations 17in a side face 18 of the grooved sheave 12 indicate the angular extentof the groove 14 for a purpose to be fully discussed hereinafter.

A bending arm 20 is pivotally linked by a pivoting link 21 to thegrooved sheave 12. A central aperture 22 in the grooved sheave 12receives a first pivot pin or trunnion 23 of the pivoting link 21. Thepivot pin 23 has a head 24 in abutment with the side face 18 of thegrooved sheave 12, thus journalling the pivoting link 21 to the groovedsheave 12. A second pivot pin or trunnion 25 of the pivoting link 21extends through an aperture 26 in the bending arm 29, and has a head 27maintaining the pivoting link 21 journalled to the bending arm 20.

The bending arm 20 includes a bending head or shoe 28 adjacent thelinkage between the bending arm 20 and the pivoting link 21. The bendinghead or shoe 28 is grooved at 30. The groove 30 is substantiallysemi-circular in cross-section and complementary to the semicirculargroove 14 in the grooved sheave 12, as is clearly shown in FIGURE 3.

A tube clamp 31 is swingably mounted on the handle 11 adjacent thegrooved sheave 12. The tube clamp 31 includes a tube engaging hookportion 32. The tube engaging hook portion 32 clainpingly engages theexterior of a tube when the tube clamp 31 is swung from an inoperativeposition (shown in FIGURE 3) to an operative position, such as theposition of the tube clamp 31 illustrated in FIGURE 4.

A prepositioning device comprising a locking collar 33 is slidablymounted on the handle 11 of the tube bender adjacent the tube clamp 31.The locking collar 33 is a split collar which may be secured to thehandle 11 in any one of a plurality of different ways, one way being bya threaded bolt 34 cooperative with a clamping wing nut 35 as shown inFIGURE 1.

A reversible bracket means 36 is freely, swingably, slidably mounted onthe handle 11 of the compound tube bender 10. An axial bore 37 throughthe reversible bracket 36 journals the reversible bracket means 36 uponthe handle 11. A surface 38 of the reversible bracket 36 abuttinglyengages the locking collar 33 for a reason to be more fully hereinafterexplained.

A one-piece bracket clip 40 is journalled to revolve within an axialaperture 41 of the reversible bracket 36. One end of the bracket-clip 40includes a first tube engaging portion 42. The tube engaging portion 42includes a generally downwardly facing, semi-circular groove 43. Thegroove 43 is complementary to the groove 14 of the grooved sheave 12, asis clearly shown in FIGURE 3 of the drawings.

A downwardly opening hook portion 44 of the tube engaging portion 42cooperates with a rearwardly opening slot 45 and a flat face 46 of thebracket-clip 40 to captively clamp a first bent portion of a tube priorto forming another bend in the tube.

An annular portion 47 of the bracket-clip 44) includes an abuttingsurface 48 which limits the entry of the bracket-clip 40 into the axialaperture 41 of the reversible bracket 36. A plurality of angulargraduations 50 on the annular portion 47 of the bracket-clip 40cooperate with a reference mark 51 on the reversible bracket means 36,as is best shown in FIGURE 2 of the drawing, whereby the bracket-clip 40may be rotated with respect to the reversible bracket means 36. Thebracket-clip 40 is secured with respect to the reversible bracket 36 bymeans of a threaded end portion 52 of the bracket-clip 40 and a knurledthreaded nut 53 cooperative therewith in a manner clearly illustrated inFIGURE 1 of the drawings.

The threaded end portion 52 of the bracket-clip 40 forms a second tubeengaging portion which is adapted to engage an end nut of a tube whenthe reversible bracket 36 is reversed end-for-end from the positionillustrated in FIGURE 1 to the position shown in FIG- URE 4. Thethreaded end portion 52 of the bracketclip 40 is shown directed towardthe grooved sheave 12 in FIGURE 4. A tube T lies within the groove 14 ofthe grooved sheave 12 and is clampingly maintained therein by the hook32 of the tube clamp 31. A flared end E of the tube T secures a sleeve Sand a threaded tube nut N on the end E of the tube T in a manner clearlyillustrated in the drawings. The threads of the threaded end portion 52and of the tube nut N are complementary, and in this manner, a bend maybe formed in the tube T adjacent the tube nut N while the tube T isengaged by the threaded end portion 52 of the bracketclip 40.

In operation, a first bend is made in a tube by first pivoting thebending arm 20 to a position above the grooved sheave 12, as is shown inFIGURE 4, and the reversible bracket 36 is swung to an out-of-the-wayposition about the handle 11. A tube is then placed in an uppermostportion of the groove 14 with the hook portion 32 of the tube clamp 31in overlying clamping engagement with the tube. The bending arm 20 ismoved to a position in which the groove 30 of the shoe 28 abuttinglystraddles the tube. As the bending arm 20 is pivoted clockwise about thegrooved sheave 12 shown in FIGURE 1, the tube is bent into the groove 14of the grooved sheave 12 until the desired bending of the tube isaccomplished. The angular bend made in the tube is, of course, indicatedby the graduations 17 on the side face 18 of the grooved sheave 12.

After a first bend has been made in the tube, a second bend may be madein the same or a dissimilar plane as the first bend by employing thereversible bracket 36 and the prepositioning device 33.

Depending on the distance between the first and second bends of the tubeand the planar relationship between the first and second bend of thetube, various adjustments of the bracket-clip 40 and the prepositioningdevice 33 may be required. For example, the tube bender 10 illustratedin FIGURES 1 through 3 of the drawings is adjusted to form a second bendin the tube which is in the same plane as the first bend of the tubewith no spacing between the respective bends. That is, the zerograduation of the plurality of graduations 50 on the annual shoulder 47of the bracket-clip 40 is directly aligned with the reference index 51on the reversible bracket means 36 whereby the groove 43 of the tubeengaging portion 42 is in axial alignment with the groove 14 of thegrooved sheave 12. When the first bend portion of the tube is placedwithin the groove 43 and the bending arm 20 is moved in a clockwisedirection with respect to the grooved sheave 12, a second bend is formedin the tube in the same plane as the first bend therein.

Furthermore, because the prepositioning device 33 is secured to thehandle 11 in the position illustrated, there is no spacing between thefirst and second tube bends. In other words, the position of theprepositioning device 33 and the reversible bracket 36 in FIGURE 1 issuch that the axis of generation of the first bend overlies the axis ofgeneration of the second bend, and spacing between the bends isprecluded.

If for any reason it is desirable to form a second bend in a tube spacedfrom a first bend therein, the wing nut 35 of the prepositioning device33 is first loosened. The prepositioning device or locking collar 33 isthen slid to the left of FIGURE 1, an amount equal to the desiredspacing between first and second bend. This movement to the left of theprepositioning device 33 causes the movement therewith of the reversiblebracket 36 and the tube engaging portion 42 thereof. The further theportion 44 of the tube engaging portion 42 is spaced from the first fiatface 15 of the grooved sheave 12, the further apart is the spacingbetween first and second tube bends. At a preselected position of theprepositioning device 33 on the handle 11, the wing nut 35 is tightened,and a second bend spaced from the first bend in the tube may be formedby the movement of the bending arm 20 in a manner heretofore mentioned.

In order to accuately preposition the locking collar 33 upon the handle11, the handle 11 may be provided with a plurality of graduations Gwhich cooperate with the leftmost edge of the locking collar 33 toindicate the spacing between adjacent bends of a tube.

It is important to note that while the locking collar 33 positions thereversible bracket 36 and the tube engaging portion 42 thereof withrespect to the grooved sheave 12, since the reversible bracket 36 isfreely slidable upon the handle 11, the same can be slipped back forreleasing the tube without disturbing the prepositioning device 33. Inthis manner a plurality of identically spaced second bends may be formedin a plurality of tubes without readjusting or remanipulating theprepositioning device 33 upon the handle 11.

Should it be necessary or desirable to form a second bend in a tubewhich is non-planar to a first bend therein, the knurled nut 53 isloosened, the bracket-clip 40 is rotated until a desired angulargraduation of the plurality of angular graduations 50 is directlyopposite to the reference index 51 on the reversible bracket 36 and theknurled nut is then tightened. In this manner, the groove 43 of the tubeengaging portion 42 is rotated with respect to the groove 14 of thegrooved sheave 12, whereupon a second bend in a plane dissimilar to theplane of a first bend may be formed. The complementary grooves 14 and 43coact with a tube inserted therein to prevent the reversible bracket 36from rotating about the handle 11, while the flat face 46 of thebracket-clip 40 coacts with a first bend in the tube to automaticallyposition the bracket-clip 40 to the preselected plane of a desiredsecond bend.

When the compound tube bender is used to form a bend located close to anut, such as the tube nut N shown in FIGURE 4, the reversible bracket 36is reversed endfor-end from the position shown in FIGURE 1 to theposition shown in FIGURE 4. The tube nut N is threaded upon thecomplementary threads of the threaded end portion 52, thereby permittingthe tube T to be bent adjacent the tube nut N. Thus, the compound tubebender 10 hereindisclosed can be used to form a bend in a tube close toa tube nut as well as to form bends anywhere along the length of thetube.

From the foregoing description of this invention, it should be readilyapparent that the com-pound tube bending device 10 provides manyadvantages heretofore lacking in known tube benders. For example, it iswell known in the prior art to employ such means as keyways to maintainand slidably position a bracket, such as the reversible bracket 36disclosed herein, upon a handle of a tube bender. Such keyways areeliminated in the instant tube bending device because the bracket-clip40 automatically positions itself in line with the grooved sheave 12when a tube is in position, i.e., when a tube is positioned within thegrooves 14 and 43, slot 45 and against the fiat face 46. No separateclamping means are required to hold a first bend of a tube in a fixedplane because of the cooperative relationship between the flat face 46,the slot 45 and the groove 43. Furthermore, because the bracket-clip 40is of a one-piece construction it provides, with the reversible bracket36, excellent support against outward pivoting when holding a tubeduring the bending thereof. That is, when a second bend is being formedin a tube, the forces exerted by the bending arm 20 against the tubetend to lift the tube engaging portion 42 in an upward counterclockwisedirection, as viewed in FIGURE 1, thereby placing extremely highstresses upon the respective journals between the reversible bracket 36,the handle 11 and the bracket-clip 40. The stresses are reduced to aminimum, once again, because of the one-piece construction of thebracket-clip 40 and the cooperative relationship thereof with thereversible bracket 36.

While example disclosures of a compound tube bending device are shownherein, it is to be understood that changes in the disclosed structuresand arrangements may be made without departing from the spirit and scopeof the invention as defined in the appended claims.

I claim:

1. A compound tube bending device comprising a handle having a groovedsheave at one end thereof, a bending arm pivotally carried by thesheave, said bending arm having a complementary groove at the pivotallyconnected end thereof, a bracket slidably and freely rotatably carriedby said handle, a clip rotatably journaled within said bracket, meansfor securing said clip in any one of a plurality of selected rotatedpositions, lockable prepositioning means slidably journaled on saidhandle, said bracket being cooperative with said prepositioning meansfor abutment therewith whereby the distance between first and secondbends in a tube may be preset, said clip including a body having an endportion adjacent said sheave, said end portion including tube engagingmeans, said tube engaging means including a groove defined by a curvedsurface portion, said groove terminating at opposite ends thereof inslots and said tube engaging means including said slots and curvedsurface portions cooperating to automatically position said cliprelative to said sheave when a first tube portion is positioned in saidgroove and slots and a second tube portion is positioned in said groovedsheave.

2. A compound tube bending device comprising a handle and a groovedsheave at one end thereof, a bending arm pivotally carried by thesheave, said arm having a complementary groove at the pivotallyconnected end thereof, a bracket slidably and freely rotatably carriedby said handle, a clip rotatably journallled within said bracket, meansfor securing said clip in any one of a plurality of preselected rotatedpositions, lockable prepositioning means slidably journalled on saidhandle, said bracket being cooperative with said prepositioning meansfor abutment therewith whereby the distance between first and secondbends in a tube may be preset, said clip including a body having an endportion adjacent said sheave, said end portion including tube engagingmeans, and said tube engaging means including a threaded end portionpredetermined for internally gripping a portion of a tube.

3. The compound tube bending device as defined in claim 1 herein saidbracket is reversibly carried by said handle.

4. The compound tube bending device as defined in claim 2 wherein saidbracket is reversibly carried by said handle.

5. A compound tube bending device comprising a handle having a groovedsheave at one end thereof, a bending arm pivotally carried by thesheave, said arm having a complementary groove at the pivotallyconnected end thereof, a bracket slidably and freely rotatably carriedby said handle and being mounted for reverse positioning thereon, a cliprotatably journalled within said bracket, means for securing said clipin any one of a plurality of selected rotated positions, a lock collardefining lockable prepositioning means slidably journalled on saidhandle, said bracket being cooperative with said lock collar forabutment therewith whereby the distance between first and second bendsin a tube may be preset, said clip including a body having an endportion adjacent said sheave, said end portion including tube engagingmeans, said tube engaging means including a groove defined by a curvedsurface portion, said groove terminating at opposite ends thereof inslots, said bracket being automatically positioned in preselected planaralignment with respect to the grooved sheave by said tube engagingmeans, and a tube clamp swingable mounted on said handle adjacent saidsheave.

References liter by the Examiner UNITED STATES PATENTS 1,665,643 4/1928Schmitt. 1,781,592 11/1930 Meier. 2,955,495 10/ 1960 Stirling.

WILLIAM FELDMAN, Primary Examiner.

1. A COMPOUND TUBE BENDING DEVICE COMPRISING A HANDLE HAVING A GROOVEDSHEAVE AT ONE END THEREOF, A BENDING ARM PIVOTALLY CARRIED BY THESHEAVE, SAID BENDING ARM HAVING A COMPLEMENTARY GROOVE AT THE PIVOTALLYCONNECTED END THEREOF, A BRACKET SLIDABLY AND FREELY ROTATABLY CARRIEDBY SAID HANDLE, A CLIP ROTATABLY JOURNALED WITHIN SAID BRACKET, MEANSFOR SECURING SAID CLIP IN ANY ONE OF A PLURALITY OF SELEACTED ROTATEDPOSITIONS, LOCKABLE PREPOSITIONING MEANS SLIDABLY JOURNALED ON SAIDHANDLE, SAID BRACKET BEING COOPERATIVE WITH SAID PREPOSITIONING MEANSFOR ABUTMENT THEREWITH WHEREBY THE DISTANCE BETWEEN FIRST AND SECONDBENDS IN A TUBE MAY BE PRESET, SAID CLIP INCLUDING A BODY HAVING AN ENDPORTION ADJACENT SAID SHEAVE, SAID END PORTION INCLUDING TUBE ENGAGINGMEANS, SAID TUBE ENGAGING MEANS INCLUDING A GROOVE DEFINED BY A CURVEDSURFACE PORTION, SAID GROOVE TERMINATING AT OPPOSITE ENDS THEREOF INSLOTS AND SAID TUBE ENGAGING MEANS INCLUDING SAID SLOTS AND CURVEDSURFACE PORTIONS COOPERATING TO AUTOMATICALLY POSITION SAID CLIPRELATIVE TO SAID SHEAVE WHEN A FIRST TUBE PORTION IS POSITIONED IN SAIDGROOVE AND SLOTS AND A SECOND TUBE PORTION IS POSITIONED IN SAID GROOVEDSHEAVE.